Valve stem grinding tool



Dec. 5, 1939. P. MURRAH VALVE STEM GRINDING TOOL Filed Feb. 17, 1939 [/7 Mag/3P Pqq/ [YUP/VH7,

1W5 14175 may Patented Dec. 5, 1939 vided which is adapted to be placed upon the .45 ically positioning the grinding disk of the tool -ly in 4, the-motorend plate =3I is provided relative to the valve in accordance with the diswith an outwardly extending rectangular po'rtance from the valve seat to the upper end .of :tion for cd-operativly and slidably engaging the valve push rod or tappet. V with parallel facing surfaces 32and 33 of the side For a consideration of what I believe to be .members .l5.and ;:l.6. The .motor is retained upon 50 mTEp v STATES P T-ear ot'rlci VALVE STEM GRINDING 7T0QL Paul Murrah, (lorinthg'Miss. 7 Application February 17, 1939, Serial No, 257,904 11 Claims. (01. s -ss This invention relates to grinding tools and, although not necessarily limited thereto, to portable tools for grinding the ends of valve stems for internal combustion engines to a proper pretool e body n /my invention and is shown fit ed into avfiveehamber .ofa cylind r bloc ustrated. in. cross-section; ,Fig. 2 isa Side levation of th to. 1; .3 is-a cross se tional vie ofa .determined length. detailvtakenmalong.the line 3. 3 and Fig. Lisa =5- The fuel intake and exhaust gas ports of incross-sectional viewQf .adetailtakenalong the ternal combustion engines are usually controlled line l4. p f by valves operated in a predetermined sequence The grinding tool comprises a circular base l0 by means of tappets or push rods driven by the havinga cylindrica P i I d pen in he eengine. For the most emcient operation of. the from wh ch adapted t fi nu l 1111 th valve engine, it is important that a proper clearance stem guide bearingpassage 12 9i an engine cylbe provided between the tappet, or push rod, and .ind. ...bl0 ;ky! he base. W .P Q iQ- 9Z 1P the end of the, valvefstem. In certain types of lower. ed e W th & p IQ 6 iCh .1 engines, the adjustment of the valve is accom- -.adap ed 0 5.6 firmly 1 1 91 n? val t 9f 2h? plished by grinding more or less metal from the cylind r; bJO K- .EXtQ l i D lTPIldiC1l1I ..fFQm end of the stem as determined by the distance the upper surface of thebase lllisa iramecombetween the valve seat in the cylinder block and prisin .apa z 0f substantially parallel side memthe upper end ortne valve tappet. Thishas hers l5 and I6 su mounted b an exter au usually necessitated the grinding of the valve threaded cylindrical head H. A valvehcldi j g s .by i or miss methods until its proper template; 1 oro erat ve th e ded nto the length was obtained. Such methods are not only head. U, up fi s l whi h fimll filte is prpwasteful but time consuming and inaccurate. vided with an inwardlytapering seat J9. for co.-

.It is anobject of this invention to provide a opera ivel re e ving .& valvem, the stem 2] v of new and improved portable tool for grinding the which is to beground. For facilitating the inends of valve stems for engines of the type resertien and removal of the valve into the togl ferred to expediently and accurately. I and for manually rotat n the valve during the It is a further object of this invention to progrinding operation diametrically opposite porvide a new and improved valve stem grinding .tions areremoved from the upper end of the tool which when once adjusted may be .used 'for teinplate sq as to provide openings, 22 exposing accurately finishing the ends of a plurality of portionsof the valve periphery substantiallyas 3 valve stems of varying lengths without readjustindicated. The upper end of the head has a ment. emi-ei eul r We 23 w t -s aped notch 4 It is a still further object of this invention at the center thereof as shown in Fig 3. E2;- to provide a portable valve stem grinding tool tending between the side frame members .liand .Which may be supported upon the engine cylin- .16 is a transverse seotiom as at ,25, having a der block and which automaticallyand accurately determines the proper amount of grindingto be done on each of the engine valves.

In accordance with the illustrated embodiment,'a portable valve stem grinding tool is pro- 26, which are oppositelydisposed with respect to .each other, are adaptedto receive the valve stem '2! and. assist inmaintaining the Valve in the operation.

cylinder block of the engine and seated upon An electric motor 28, having a grinding disk the valve seat therein for the particular valveto be fitted, with means provided on the tool for a for slidable movement vertically between the side holding the valve and other means for automatirame members 1-5 and i6. As shown more clearnovel and my invention, attention is directedltothe .following description and the claims appended thereto taken in connection with the accompanying drawing.

11am the. members 11 and -15 and is secured to. the mo r ndpla a l v-tatnlu a i .0! serewstt. T e n ate 1$ rl t edw th sideflweesitans In the drawing 1 l i ea itbe .3 and. li f re flai efl term te-e ua d V- sh aped notch .26 therein. The notches 24 and .theIrame .Iby meansof the plate .34 which .overproper position in'the" tool the grinding 2-9 provided on the end of the shaftilfl, is mounted for the grinding disk. A gage rod 39 secured to the lower flange 38 of the plate 34 extends axially through the base l0 and the cylindrical portion II, the end thereof being adapted to engage with the upper end of the valve tappet 40 of the engine and position the grinding disk relative to the valve to be ground as will be hereinafter described.

The tool is adjusted by turning the adjustable template so that the distance from a predetermined point on seat M of the base It] to a corresponding predetermined point on the seat I9 of the template is equal to the distance from the lower end of the gage rod 39 to the upper surface of the grinding disk 29. To correct for the necessary clearance to be allowed between the valve tappet and the lower end of the valve stem, the template is then moved the requisite 'few thousandths of an inch toward the grinding disk. For facilitating this latter adjustment, co-operating micrometric scales may be provided on the head I! and the lower edge of the template l8, as indicated at 4| and 42. After the tool is adjusted, the template may be made fast with respect to the head by tightening a suitably arranged set screw 43 contracting the lower rim of the template upon the head.

It is understood that, prior to the stem grinding operation, the valve face is first ground or otherwise fitted into the seat of the cylinder block in the conventional manner. The tool is then inserted into the valve chamber with the face 14 firmly resting on the valve seat of the cylinder block. The motor and grinding disk are then pushed downwardly until the end of the gage rod.

39 contacts with the upper surface of the valve tappet 49. It is obvious that in this position the distance from the valve seat on the template l8 to the upper surface of the grinding disk 29 will be exactly equal to the distance from the valve seat of the cylinder block to the upper surface of the valve tappet 31 less the amount of correction made for clearance. The valve may then be inserted into the tool and with the motor driving the disk 26 the lower end-ofthe valve stem 2| may be ground no more than the requisite amount. During the grinding operation the valve may be rotated by hand or by any other suitable means to insure the flat grinding of the stem end until the face of the valve rests squarely upon the seat l9of the-template. The tool is then shifted to the next valve seat for finishing the stem of the valve corresponding thereto.

As is well known by those skilled in the art, the distance between the various valve seats and the corresponding tappets in an engine cylinder block will vary appreciably, but, by-the use of this tool, each valve stem is ground accurately to the proper length as is determined automatically by the mere insertion of the tool into each valve chamber. As the tool is moved from one valve chamber to the next and the grinding disk and motor moved downwardly until the gage rod 39 comes into contacting relationship with the corresponding valve tappet, each valve stem may in turn be finished with no separate measurements or other adjustments of the tool required during the course of an engine valve stem grinding job.

It is obvious that after a certain number of valve stems have been ground, the surface of the grinding disk 26 may become somewhat worn and correspondingly decreased in diameter. Therefore, it is desirable that the initial adjustment of the tool be checked periodically and that the template l8 be readjusted to correct for any wearing of the grinding disk.

It is pointed out that this invention is not necessarily limited to valve grinding tools, but

it is obvious that by simple modifications which may be made by one skilled in the art, it may be adapted for grinding other articles to a proper length as determined by the distance between two spaced apart points between which such article is to extend. Furthermore, while I have shown an electric motor for driving the grinding disk 26, it is obvious that any other suitable 'driVing means may be substituted therefor, such as a manually operable crank mechanism. A remote source of power. may also be coupled to the grinding disk by means of a suitable flexible shaft.

It is further obvious that in lieu of the grinding disk 26, any other suitable cutting implement,

may be used for finishing the end of the valve stem.

While I have shown and described the principal of operation of my inventionin what I consider to be the preferred embodiment thereof, I desire to have it understood that it is not limited to any precise construction or combination of elements as set forth, but includes within its scope whatever modifications come within the spirit of the appended claims.

What I claim as new and desire to secure by Letters Patent of the United States, is:

1. A valve stem grinding tool comprising a base having a face adapted to co-operatively rest on the valve seat of a cylinder block, a cylindrical portion depending from said base and adapted to snugly fit into the valve stem guide bearing passage in said cylinder blockga frame member extending upwardly from the upper surface of said'base, a template secured to the upper end of said frame member for supporting a valve axially parallel with respect to the valve seat of said cylinder block, a grinding disk, means for slidably supporting said grinding disk on said frame member for movement in the axial direction with respect to the stem of said valve, a

gaging rod operatively secured to said grindingis disk supporting means and adapted to extend through said base and to engage with the valve' tappet of the cylinder block and position said grinding disk with respect to said template.

2. A valve stem grinding tool comprising a base having a face adapted to co-operatively rest on the valve seat of a cylinder block, a cylindrical portion depending from said base and adapted to fit snugly into the valve stem guide bearing passage in said cylinder block, a frame member secured to the upper surface of said base, means for supporting a valve on said frame member, a grinding disk slidably arranged on said frame member and movable in the axial direction with respect to the stem of the valve and into engageblock for positioning said grinding disk relative said base, a template provided on the upper end of said frame member having a seat for supporting, a valve with the stem thereof depending downwardly "therefrom, agrinding disk mounted on said frame member and slidable thereon in the axial direction with respect to the valve stem and means for positioning said grinding disk relative to the valve seat of said template in accordance with the distance from the valve seat of the cylinder block to the valve tappet therein.

4. A valve stem grinding tool comprising a frame, a base on said frame adapted to co-operatively rest on the valve seat of an engine cylinder block, adjustable means for supporting a valve on said frame, a grinding disk slidably supported on said frame and movable in the axial direction with respect to the stem of the valve supported on said frame and into engagement therewith, a gaging rod movable with said grinding disk adapted to extend into the cylinder block and engage with the corresponding valve tappet therein for positioning said grinding disk on said frame with respect to said valve supporting means.

5. A valve stem grinding tool comprising a frame having a base adapted to co-operatively rest on the valve seat of an engine cylinder block, a template on said frame for co-operatively receiving a valve, a grinding disk slidably arranged on said frame member and movable in the axial direction with respect to the stem of said valve and into engagement therewith and means for automatically positioning said grinding disk with respect to said template in accordance with the distance from the valve seat to the corresponding tappet in said cylinder block.

6. A valve stem grinding tool comprising a frame, means on said frame for positioning the head of the valve to be ground relative to the valve seat of a cylinder block, a grinding disk movably mounted on said frame, and gaging means secured to the grinding disk mounting for automatically positioning said grinding disk on said frame into grinding relationship with the end of the valve stem as determined by the distance between said valve seat and the corresponding valve tappet measured by said gaging means.

7. A valve stem grinding tool comprising a frame having a portionadapted to co-operatively rest on a valve seat of a cylinder block, a rotatable grinding disk movably mounted on said frame, supporting means on said frame for a valve including means for guiding and limiting the movement of said valve toward said grinding disk, and gaging means secured to the grinding disk mounting for movement therewith for measuring the distance from said valve seat to the corresponding valve tappet and positioning said grinding disk accordingly relative to said valve supporting means.

8.A valve stem grinding tool comprising a frame having a pair of spaced apart parallel members, means for holding a valve in said frame with the stem thereof extending parallel with said parallel members, a grinding disk slidably mounted on said parallel members, a measuring surface on said frame, and gaging means secured to said grinding disk mounting and slidable therewith for adjustingthe position of said grinding disk relative to said valve holding means in accordance with the amount of grinding to be performed on the stem of said valve as measured by the distance between said gaging means and said measuring surface.

9. A tool for grinding an article to a predetermined length in accordance with the spacing between two relatively fixed points, said tool comprising a frame, a grinding disk movably mounted on said frame, means for supporting the article to be ground upon said tool including means for guiding and limiting the movement of the article toward said grinding disk, means for holding said supporting means fixed with respect to one of said points and gaging means fixedly secured to the grinding disk mounting for move- 'ment therewith for measuring the distance fro-m said one point to the second of said points and positioning said grinding disk accordingly relative to said article holding means.

10. A tool for grinding an article to a prede- 11. A grinding tool comprising a frame, a roance with the measured distance between said measuring surface and a point on said gaging means.

PAUL MURRAH. 

